ES2955138T3 - Radially contractile flexible textile tube - Google Patents

Abstract

Radially retractable textile tube for enclosing elongated objects, characterized by having an outer layer (2) of radially retractable wear-resistant material and at least one inner layer (4) of thermally insulating material. (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Radially contractile flexible textile tube

The present invention relates to a radially contractible flexible textile tube for covering elongated objects according to DE 297 10583 U1.

From EP 0520 473 A1 a flexible multi-layer foam tube is known which shrinks when heat is applied. From document EP 1685 285 B1 a two-layer radially contractile textile flexible tube is known, with an upper fabric layer and a lower fabric layer, in which the fabric layers are connected by their edges to each other with threads. of union warp, thus forming a flexible tube. These flexible tubes are used, for example, in the automotive industry as mechanical reinforcement and to increase the abrasion resistance of rigid tubes and flexible tubes. To do this, they are stretched over elongated objects, such as rigid tubes, flexible tubes or foam tubes, and then contracted. In this way, protection against mechanical abrasion is achieved. Foam pipes, for example EPDM, are also used for insulation. Currently2, foam pipes, for example based on EPDM, are used in practice to protect automobile ducts against heat loss or cold influences. These can be, for example, cooling fluid hoses. They are also used for the coating of electrical cable bundles. Insulation is used, among other things, to prevent possible performance losses of a vehicle's propulsion system, which may occur due to heat loss. On the one hand, the aforementioned flexible EPDM foam tubes have a high insulating capacity, but on the other hand they are extremely susceptible to mechanical effects such as abrasion.

Due to increasingly tight installation spaces in automotive engineering, the likelihood that foam ducts used for thermal insulation in the engine compartment of a car come into contact with other components, e.g. hot or abrasive , she's very tall. Depending on the intensity of the contact, high abrasive forces can act on the foam duct, which can lead to rapid destruction of the foam duct and thus severely limit the insulating effect.

The objective of the present invention is to propose a radially contractile flexible textile tube for the coating of elongated objects, with which the drawbacks known from the state of the art are avoided, or at least greatly reduced.

The task is solved with a flexible tube according to claim 1, namely with a radially contractible textile flexible tube for covering elongated objects, which has an outer layer of contractile, abrasion-resistant material and at least one inner layer of material. thermally insulating, the material of the at least one inner layer (4) being inflatable when applying heat, which is characterized in that the outer layer and the at least one inner layer are joined at some points to each other by means of a textile ligament or of seams. A flexible tube of this type according to the invention can be placed by shrinkage, with a defined thermal conductivity and at the same time a high mechanical resistance to abrasion, on rods, flexible tubes, cable bundles, ducts, profiles, pipes, which must be thermally insulated and run the risk of abrasion, which do not necessarily have to be elongated, but can present bends, in a single operation and be firmly fixed therein in an essentially immovable manner. This advantageously eliminates the need to subsequently place several layers on top of each other. Deterioration of the insulating layer, for example the EPDM foam tube, which is at risk of abrasion, is also prevented. Such a flexible tube can, for example, be designed so that it is woven with multi-filament warp threads extending axially, and with contractile single-filament weft threads extending in the perimeter direction. When the flexible tube according to the invention shrinks, the outer layer of the coating tends to narrow the flexible tube radially due to the shrinking single filament weft yarns. It is understood that, for this purpose, the outer layer has, according to the invention, the property of shortening in the perimeter direction to cause a narrowing in the radial direction.

To keep the assembly effort during processing as low as possible, it is preferable that the protective hose can be assembled in a single operation during production. For this reason, preference is given to the flexible textile tube according to the invention, since its multi-layer structure can be produced in a single operation, thereby eliminating the need for a large subsequent assembly effort in which stretch several layers on top of each other.

This provides the great advantage that, simultaneously with the contraction of the outer layer, a swelling of the inner layer is achieved, which in turn allows a fixed arrangement of the coating on the elongated object. In an advantageous embodiment of the invention, the lining is configured such that the outer layer and the at least one inner layer are connected to each other at certain points by means of a textile ligament, sewing them together. This embodiment further simplifies the assembly of the flexible tube according to the invention, since its two layers cannot move relative to each other, nor detach from each other during assembly. Consequently, the assembly is safer and more reliable.

In another advantageous embodiment variant of the invention, the flexible tube is configured such that the outer layer and the at least one inner layer are connected to each other along areas spaced apart from each other that extend axially. In this way a compact and therefore more stable structure of the flexible tube can advantageously be achieved.

In yet another advantageous embodiment of the invention, the flexible tube is configured so that between the outer layer and the at least one inner layer, in the part of the chambers located between the zones, a shaped filling material is arranged. of threads, ribbons, preferably foam. This design allows an essential increase in the insulating properties of the flexible tube according to the invention. For this purpose, a wide variety of suitable insulating materials are available in the form of threads and tapes, particularly foam.

In another advantageous embodiment of the invention, the flexible tube is designed so that the outer layer and the at least one inner layer consist of a spun, knitted or braided fabric. This advantageously allows a very economical production of the flexible tube according to the invention.

In yet another advantageous embodiment of the invention, the flexible tube is configured such that it has multi-filament yarns extending axially, and single-filament and multi-filament yarns extending in the perimeter direction. With the addition of multi-filament yarns, which extend in the perimeter direction, for example, in a floating manner with the single-filament yarns, the thermal conductivity of the flexible tube can be controlled, on the one hand. On the other hand, the contraction process can be influenced. Additionally, this advantageous refinement results in more uniform shrinkage patterns. The so-called warp gaps are avoided. The stability of the joints increases.

In another advantageous variant of the invention, the flexible tube is designed so that the outer layer is coated or impregnated with a product that increases wear resistance. With this advantageous measure, the desired useful life in each case of the flexible tube according to the invention can be achieved.

In yet another advantageous embodiment of the invention, the flexible tube is configured so that the at least one inner layer is coated or impregnated with a product that increases thermal conductivity. With this advantageous measure, the insulating capacity of the flexible tube according to the invention can be increased as desired in each case.

These products mentioned above correspond to the so-called sizing baths known from the state of the art. Products to improve thermal conductivity, mechanical strength or cold cutting capacity can be applied, for example, by padding, scraping or spraying.

In another advantageous embodiment of the invention, the flexible tube is configured so that it is composed, at least in part, of packed filaments. This embodiment offers the advantage that, depending on the need for optimization with respect to thermal conductivity, mechanical strength and cold cutting capacity for the desired application, the individually sized filaments positively influence the performance of the tube. flexible according to the invention.

In another advantageous embodiment of the invention, the flexible tube is designed in such a way that the at least one inner layer is moistened on the inside with an adhesion agent or an adhesive. This can further increase the secure attachment of the flexible tube according to the invention to the selected elongated object, especially when it is used in a vibrating environment.

In another advantageous variant of the invention, the flexible tube is configured so that the at least one inner layer is in the form of small ribbons, in particular foam. Within the inner layer in the form of tapes, a greater inclusion of air can be advantageously achieved, compared to a normal yarn, whereby the insulating effect can be increased even further.

For a better understanding of the invention and to show how it can be carried out, it is briefly explained below in more detail in view of an embodiment example and with the help of a drawing. It is shown in

Figure 1 is a very schematic perspective view of a section of a flexible tube with an approximately central longitudinal cut according to the invention, arranged around an elongated and already partially shrunken object;

Figure 2 in schematic view, a cross section of the flexible textile tube with a detail X;

Figure 3 is a highly schematic perspective view of a section of an embodiment of a flexible tube according to the invention;

Figure 4 is a very schematic perspective view of a section of a flexible tube according to the invention opened longitudinally approximately in the center, analogous to that of Figure 1, without the elongated object;

Figure 5 is a highly schematic perspective view of a section of a radially contractile flexible textile tube according to the invention with longitudinal chambers.

Figure 1 shows a flexible tube 10 according to the invention cut longitudinally approximately in the center, with an outer layer 2 and an inner layer 4. The outer layer 2 is intended to represent an abrasion-resistant coating surrounding the inner layer insulator 4. In a zone III, the flexible tube 10 has already contracted around an elongated object, in this case, for example, a pipe 1.

In zones I and II, the flexible tube 10 still has an inner diameter larger than the outer diameter of the pipe 1. At the beginning of assembly, the still unshrinked flexible tube 10 according to the invention with the diameter according to zone I is pushed on pipe 1. Heat is then applied to it from the outside, for example by means of a hot air flow oven, so that it shrinks on the pipe, with the result that, as the transition in the area is intended to show, II, it shrinks and fits perfectly to the pipe 1. In zone III, the flexible tube 10 is completely shrunken and firmly seated on the pipe 1. It can be clearly seen that the inner insulating layer 4 is thicker than the outer layer abrasion resistant 2.

In zone III, the flexible tube 10 has already been completely shrunk and fixed in the pipe 1, with the inner insulating layer 4 firmly fitting. Between the inner insulating layer 4 and the pipe 1, an adhesive can also be applied to fix the tube. flexible even more securely in pipe 1.

In zone II, the contraction process will be illustrated. By heating the flexible tube 10 pushed onto the pipe 1, it contracts. In the process, the diameter of the flexible textile tube 10 narrows, while at the same time the wall thickness of the inner insulating layer 4 and the outer abrasion-resistant layer 2 increases.

Advantageously, the inner heat-insulating layer 4 has a wall thickness of between 0.5 and 6 mm. The abrasion-resistant outer layer 2 of the flexible textile tube 10 has the function of protecting the insulating inner layer 4 against mechanical effects coming from the outside.

In Figure 2, a flexible tube 10 according to the invention is shown, here, for example, transversely oval, with an outer layer 2 and an inner layer 4, which are connected to each other by means of a plurality of joints 26, for example , in the form of a woven ligature or a seam or a braided connection. When using several inner insulating layers 4, the connection can also be provided between said layers, as mentioned before. In this case, the connections 26 extend not only perimeter along the flexible textile tube 10, but also in its longitudinal direction, in order to achieve a uniform connection between the different layers. Preferably, these connections 26 are created by joining during the manufacturing of the flexible textile tube 10. The flexible tube 10 according to the invention can be manufactured by weaving, knitting or braiding. As connection 26, a subsequent fixation by means of an adhesive technique or by sewing the different layers would also be conceivable. In Figure 2, lower right, the arrangement of a connection 26 is shown enlarged.

Figure 3 shows a schematic representation of a flexible textile tube 50 as it appears after being finished using a suitable sizing bath to improve thermal conductivity and mechanical resistance. Here, a section of the flexible textile tube 50 is shown enlarged to show that the sizing bath (which is a fluid for finishing a textile object, see above), hereinafter referred to as "coating", impregnates the flexible tube. textile layers 50. The reference number 60 identifies here, for example, the textile layers of the tube that are completely impregnated, while the reference number 70 identifies the textile layers in their unfinished form (before the bath of right away).

It would also be conceivable to moisten only the entire surface of the flexible textile tube and thus dispense with a complete impregnation of the entire flexible textile tube. By wetting the surface, the inner layers are not "hardened" by the sizing (sizing bath), thus maintaining the volume of the inner layer yarns and better insulation values can be achieved. You also get the advantage of being able to save finishing material.

Figure 4 shows a very schematic perspective view, analogous to Figure 1, of a section of a flexible tube according to the invention cut longitudinally approximately in half.

The figure shows a very schematic perspective view of a section of a radially contractible flexible textile tube 20 according to the invention with an outer layer 22 and an inner layer 24, as well as with longitudinal chambers 21 located between both and partially filled with filler threads. 23. The inner layer 24 surrounds an inner space 27 in which elongated objects (not shown) can be accommodated, such as tubes, flexible tubes, cables, etc. and which can be covered with the flexible tube 20 according to the invention. Once the flexible tube 20 according to the invention has been “stretched” around an elongated object (Figure 1), it can be contracted by means of heat so that it fits firmly around the elongated object and fixes it there. The inner surface 29 of the inner layer 24 can also advantageously be provided with an adhesive, through which even better adhesion of the flexible tube 20 to the elongated object during shrink fit can be achieved. Some of the chambers 21 filled in the exemplary embodiment according to Figure 5 contain filling material 23 in the form of threads, tapes, preferably foamed material, by means of which the insulating capacity of the flexible tube 20 can be considerably increased.

The outer layer 22 and the inner layer 24 of the flexible tube 20 according to the invention are, for example, woven, as shown in Figure 5, and connected to each other in the areas 12, for example, by means of ligatures. woven 26. Between the longitudinally extending zones 12, the chambers 21 are arranged. On the outside of the outer layer 22 there are threads of a linen weave L 1/1, as indicated by - I - I - I - I -, in which the flexible tube 20 according to the invention is, for example, woven. However, other ligature patterns can also be used. However, the flexible tube can also be knitted or braided. The outer layer 22 is made of abrasion-resistant heat-shrinkable material and the inner layer 24 of heat-insulating material.

Filling threads 23 arranged in the chambers 21 are additionally used for thermal insulation of the inner layer 24. In FIG. 5, a "filling" of a chamber 21 in the form of, example, curly threads 23. For this, the corresponding chamber is shown cut at point "S". However, It is also possible to use a wide variety of other filling materials. For example, the stretched threads 231, represented at point T 23 “exposed”, are introduced into a chamber 211. In addition, flexible tubes made of any suitable thermal insulation material can be used, also in the form of fleece or tape. In the present exemplary embodiment, a flexible tube 20 with an inner layer 24 is shown. However, according to the invention, several inner layers 24 can also be arranged, one on top of another or one inside another as layers of onion, for example, to increase the thermal insulation capacity of the flexible tube 20.

Claims (12)

1. Radial contractile flexible textile tube for covering elongated objects, which has the following characteristics: a) an outer layer (2) of contractile material resistant to abrasion and b) at least one inner layer (4) of thermally insulating material the material of the at least one inner layer (4) being inflatable when heat is applied, characterized by The outer layer (2) and the at least one inner layer (4) are joined together by a textile ligature (26) or sewing. 2. Flexible tube according to claim 1, characterized in that the outer layer (2) and the at least one inner layer (4) are joined together along areas (12) that extend axially, the areas (12) being ) distanced from each other. 3. Flexible tube according to claim 2, characterized in that between the outer layer (2) and the at least one inner layer (4), in the part of the chambers (21) located between the areas (12), the filling material (23) in the form of threads, tapes, preferably foam. 4. Flexible tube according to one of claims 1 to 5, characterized in that the outer layer (2) and the at least one inner layer (4) are made in the form of woven, knitted or braided material. 5. Flexible tube according to one of claims 1 to 4, characterized by having threads with several filaments that extend axially and threads with a single filament or multiple filaments that extend perimeter. 6. Flexible tube according to one of claims 1 to 5, characterized in that the outer layer (2) is coated or impregnated with a product that increases wear resistance. 7. Flexible tube according to claim 6, characterized in that the at least one inner layer (4) is coated or impregnated with a product that increases thermal conductivity. 8. Flexible tube according to one of the preceding claims, characterized by being formed, at least partially, by tightened threads. 9. Flexible tube according to one of the preceding claims, characterized in that the at least one inner layer (4) is moistened from the inside with an adhesion agent or an adhesive. 10. Flexible tube according to one of the preceding claims, characterized in that the at least one inner layer (4) is formed in the form of tapes, especially foam. 11. Flexible tube according to one of the previous claims, characterized by having a thermal conductivity < 0.3 W/m x K. 12. Flexible tube according to one of the preceding claims, characterized by having a wall thickness in the range of 1 to 8 mm.